1. Field of the Invention
The invention is directed to a method for preparing an active oxidation catalyst, and more particularly to a catalyst useful in the oxidation of alpha, beta, unsaturated carboxylic aldehydes to the corresponding acids, as well as the production of unsaturated aldehydes and acids from the corresponding alcohols and olefins.
2. Description of the Prior Art
The prior art methods for preparing oxidation catalysts useful in the preparation of unsaturated carboxylic acids and aldehydes include a step which results in the formation of inactive molybdenum compounds. One example of such a prior art method is disclosed in U.S. Pat. No. 3,965,163. In this method, a suitable source of antimony such as antimony trichloride is dissolved in hydrochloric acid and combined with phosphomolybdic acid. To this acidic solution is added a suitable source of tungsten such as tungsten trioxide. The resulting mixture is dried and calcined to form a catalyst having the following empirical formula: EQU Sb.sub.1 Mo.sub.12 W.sub.1 P.sub.1 O.sub.41.5
Other prior art references which disclose similar methods for preparing oxidation catalysts containing molybdenum include U.S. Pat. Nos. 3,875,220; 3,925,464; 3,976,688; 3,998,877; 4,017,423; 4,042,533; 4,042,625; 4,045,478; 4,051,179; 4,070,397; 4,072,708; 4,075,123; 4,075,124 and 4,075,244 and U.K. Pat. No. 1,465,916.